Periodic Reporting for period 2 - MYSpace (The role of vision on perceptual space representation)
Période du rapport: 2022-07-01 au 2023-12-31
The brain can integrate sensory signals to improve our precision in response to external input and produce optimal actions. Integrated spatial representations between sensory modalities are crucial to interact with objects and others. The visual experience has a key role for integrating sensory signals in a coherent spatial frame. How space representation develops when vision is absent, as in the case of blind infants, is still unclear.
MYSpace identifies the specific developmental periods when visual experience is crucial in establishing multisensory associations between vision and other senses. Blind and sighted infants, children, and adolescents take part into longitudinal and cross-sectional studies to identify deviation from the typical developmental trajectories of spatial skills.
Specifically, MYSpace focuses on developing audio and tactile multisensory spatial representations, crucial modalities to interact with objects and others. As an outcome, MYSpace aims to provide a new methodology to restore the integrated spatial representations of blind infants through multisensory (MS) training.
Advanced methods in psychophysics and neuroscience (high-density EEG and MRI), modeling, and high-resolution motion tracking analysis are used to investigate:
- the role of vision on the development of independent (Obj. 1) and MS (Obj. 2) audio and tactile spatial representations at the behavioral and cortical levels;
- the visual cortex involvement in the spatial processing when vision is absent (Obj. 3);
- the benefit of MS training to recover spatial impairments (Obj. 4).
By elucidating these aspects, the project bridges a gap in the knowledge of spatial representations and determines how visual experiences shape their development. It also provides a new methodology to restore the coherent spatial representations of blind infants.
MYSpace identifies the specific developmental periods when visual experience is crucial in establishing multisensory associations between vision and other senses. Blind and sighted infants, children, and adolescents take part into longitudinal and cross-sectional studies to identify deviation from the typical developmental trajectories of spatial skills.
Specifically, MYSpace focuses on developing audio and tactile multisensory spatial representations, crucial modalities to interact with objects and others. As an outcome, MYSpace aims to provide a new methodology to restore the integrated spatial representations of blind infants through multisensory (MS) training.
Advanced methods in psychophysics and neuroscience (high-density EEG and MRI), modeling, and high-resolution motion tracking analysis are used to investigate:
- the role of vision on the development of independent (Obj. 1) and MS (Obj. 2) audio and tactile spatial representations at the behavioral and cortical levels;
- the visual cortex involvement in the spatial processing when vision is absent (Obj. 3);
- the benefit of MS training to recover spatial impairments (Obj. 4).
By elucidating these aspects, the project bridges a gap in the knowledge of spatial representations and determines how visual experiences shape their development. It also provides a new methodology to restore the coherent spatial representations of blind infants.
MYSpce project aims to identify the critical period(s) for the development (and the recovery) of multimodal space representation in sighted and blind children. In this reporting period, we have pursued these goals by conducting experiments to determine the role of vision in developing independent audio and tactile modalities (Obj. 1). We demonstrated that blind infants localize audio signals on their hands as sighted infants, while they localize tactile signals differently when their hands are crossed. These findings, published on Current Biology [1], suggest that blind infants weigh differently the body features compared to sighted. We replicated the same EEG experiment to see the cortical mechanisms involved (paper in preparation – Obj. 3). Our results show that in sighted infants, the tactile remapping neural processes on external space were already developed. However, this was not the case for blind infants. We conducted further studies to investigate spatial processing in sighted and blind children considering body position in space [2,3,4], evidencing a late development of spatial audio processing assessing body change in the space in sighted children. Blind children however, show impairments in this process. We also developed a new method to investigate spatial orientation in virtual reality through psychophysics, published in Behavior Research [5].
Moreover, we have investigated audio-tactile integration in sighted and blind children with different experimental paradigms (Obj. 2, 3). Results suggest that MS integration is already evident in blind infants at the beginning of their life but is less intense than in sighted infants [1]. However, investigating more complex paradigms such as the ventriloquist task, the rubber hand illusion, and the temporal binding window, the findings evidenced in infants can extend into school-age period (papers in preparation). These data agree with the findings that shows the visual cortex role in MS space processing at the neural level [6]. However, measuring alpha activity in sighted and blind children (Obj. 3), we showed that the maximal differentiation between sighted and blind children occurs after three years of age [7]. Therefore, this should be a possible sensitive period for intervention. Lastly, we have started investigating the benefit of MS training to recover spatial impairments in blindness (Obj. 4). To this goal, the PoC called iReach (started in January 2023) has been approved for developing and commercializing a MS device for blind infants. We also developed a new technology to explore audio-tactile neural correlates in infants [8].
[1] Multisensory spatial perception in visually impaired infants. Gori, M. et al. Current Biology 2021
[2] The development of allocentric spatial frame in the auditory system. Bollini A., et al. J Exp Child Psychol. 2021
[3] The causal role of vision in the development of spatial coordinates: evidence from visually impaired children. Bollini A., et al. JEP: Human Perception and Performance 2023
[4] The development of adaptation aftereffects in the vibrotactile domain. Domenici N., et al. JEP Gen. 2022
[5] The Suite for the Assessment of Low-Level cues on Orientation (SALLO): The psychophysics of spatial orientation in virtual reality. Esposito D., et al. Behav Res 2023
[6] Multisensory representations of space and time in sensory cortices. Gori M., Bertonati G., et al. Hum Brain Mapp. 2023
[7] Sensitive period for the plasticity of alpha activity in humans. Campus C., et al. Dev. Cog. Neur. 2021
[8] Dr-MUSIC: An Effective Device for Investigating Multisensory Mechanisms during Development with EEG recordings. Bollini A., Vitali H., et al. IEEE EMBC 2023
Moreover, we have investigated audio-tactile integration in sighted and blind children with different experimental paradigms (Obj. 2, 3). Results suggest that MS integration is already evident in blind infants at the beginning of their life but is less intense than in sighted infants [1]. However, investigating more complex paradigms such as the ventriloquist task, the rubber hand illusion, and the temporal binding window, the findings evidenced in infants can extend into school-age period (papers in preparation). These data agree with the findings that shows the visual cortex role in MS space processing at the neural level [6]. However, measuring alpha activity in sighted and blind children (Obj. 3), we showed that the maximal differentiation between sighted and blind children occurs after three years of age [7]. Therefore, this should be a possible sensitive period for intervention. Lastly, we have started investigating the benefit of MS training to recover spatial impairments in blindness (Obj. 4). To this goal, the PoC called iReach (started in January 2023) has been approved for developing and commercializing a MS device for blind infants. We also developed a new technology to explore audio-tactile neural correlates in infants [8].
[1] Multisensory spatial perception in visually impaired infants. Gori, M. et al. Current Biology 2021
[2] The development of allocentric spatial frame in the auditory system. Bollini A., et al. J Exp Child Psychol. 2021
[3] The causal role of vision in the development of spatial coordinates: evidence from visually impaired children. Bollini A., et al. JEP: Human Perception and Performance 2023
[4] The development of adaptation aftereffects in the vibrotactile domain. Domenici N., et al. JEP Gen. 2022
[5] The Suite for the Assessment of Low-Level cues on Orientation (SALLO): The psychophysics of spatial orientation in virtual reality. Esposito D., et al. Behav Res 2023
[6] Multisensory representations of space and time in sensory cortices. Gori M., Bertonati G., et al. Hum Brain Mapp. 2023
[7] Sensitive period for the plasticity of alpha activity in humans. Campus C., et al. Dev. Cog. Neur. 2021
[8] Dr-MUSIC: An Effective Device for Investigating Multisensory Mechanisms during Development with EEG recordings. Bollini A., Vitali H., et al. IEEE EMBC 2023
The project is unique and innovative as it develops a new approach to studying space representation. MYSpace investigates infants and children at different ages to determine how audio and tactile systems develop, how they are integrated to create a coherent spatial representation, and how they are processed in relation to body position. Starting with the study of the specific developmental stages in which spatial skills are acquired in sighted children, the project wants determine the temporal window for their development in the blind children, and the critical periods for their recovery. Longitudinal and cross-sectional studies combining psychophysics and neurophysiology methods (high-density EEG and MRI) with MS modeling are performed to cover the main stages of the sensory development in sighted and blind children. As an outcome, MYSpace provides a new methodology to restore the integrated spatial representations of blind infants through multisensory training sessions.
MYSpace pioneers a new area of research that links child development, blindness, cortical reorganization, and rehabilitation. My ten years of experience with psychology and technology for children with and without visual impairment, and the two European projects I have coordinated on this topic have taught me the necessity to have a spatial representation model. This is crucial to understand how space representation and cortical reorganization work in our brain, and to develop useful training sessions.
These neuroscientific findings of MYSpace are helpful for i) Creating a new, innovative, user-centered rehabilitation and sensory substitution technology based on MS feedback. ii) The development of new products by small companies, which improves the competitiveness of the European industry. iii) Rehabilitation to improve impaired spatial representations for individuals with visual and motor impairments.
MYSpace pioneers a new area of research that links child development, blindness, cortical reorganization, and rehabilitation. My ten years of experience with psychology and technology for children with and without visual impairment, and the two European projects I have coordinated on this topic have taught me the necessity to have a spatial representation model. This is crucial to understand how space representation and cortical reorganization work in our brain, and to develop useful training sessions.
These neuroscientific findings of MYSpace are helpful for i) Creating a new, innovative, user-centered rehabilitation and sensory substitution technology based on MS feedback. ii) The development of new products by small companies, which improves the competitiveness of the European industry. iii) Rehabilitation to improve impaired spatial representations for individuals with visual and motor impairments.